Peeling machine for fruit and vegetables



Aug. 22, 1961 R. M. MAGNUSON FEELING MACHINE FOR FRUIT AND VEGETABLESOriginal Filed Aug. 17. 1953 6 Sheets-Sheet 1 FIG. 1.

IMVz/VTO/i GENEV/El/E MAGNUSON EXECUTQ/X OF THE ESTATE O ROVM MAGNUSO/V,DECEASED By M4 47'7'OKWEYJ 22, 1961 R. M. MAGNUSON 2,997,085

FEELING MACHINE FOR FRUIT AND VEGETABLES Original Filed Aug. 17, 1953 6Sheets-Sheet 3 GENE V/E VE MAGNUSON 762 EXECUT/P/X OF THE E$7I4TE O ROYM. MAGNUSON, DECEASED Y all 1/ ATTOPN VS Aug. 22, 1961 R. M. MAGNUSONFEELING MACHINE FOR FRUIT AND VEGETABLES 6 Sheets-Sheet 4 Original FiledAug. 17, 1953 ATTOR EYS Aug. 22, 1961 R. M. MAGNUS'ON FEELING MACHINEFOR FRUIT AND VEGETABLES 6 Sheets-Sheet 5 Original Filed Aug. 17, 1953 jINVENTOR.

5 mm M GENEVIEVE M V: 0 R F o M M 5 L A, 1 v \i r n 0 E m m 0 H N M 0 0SJT W Wm M M time Patented Aug. 22, i961 2,997,085 PEELlNG MACHINE FORFRUIT AND VEGETABLES Roy M. Magnuson, deceased, late of Saratoga,Calif., by Genevieve I. Magnuson, executrix, Saratoga, Calif., assiguor,of one-half to California Packing Corporation, a corporation of NewYork, one-quarter to Genevieve I. Magnuson, and one-quarter to GenevieveI. Magnuson, Robert Magnuson, and Lois J. Fox, as trustees Originalapplication Aug. 17, 1953, Ser. No. 374,752, now Patent No. 2,910,392,dated Oct. 27, 1959. Divided and this application Nov. 14, 1958, Ser.No. 773,973

13 Claims. (Cl. 146-47) This application is a division of the co-pendingapplication of Roy M. Magnuson, Serial No. 374,752 filed August 17,1953, now Patent No. 2,910,392.

The present invention is concerned with the peeling of fruit andvegetable articles, and relates more particularly to new means forloosening and removing the skin in an advantageous and automatic mannerwithout objectional oxidizing, charring or the like.

Previous high temperature processes on fruit and vegetable articles havebeen concerned with conditioning the skin thereof for removal, and havenot attempted the actual separation of the skin from the body of thefruit or the actual removal of the skin. In the present invention, inaddition to conditioning of the skin, actual skin or peel separation orremoval is effected automatically, and in production operation all ofthe articles, or a high percentage of the articles, will have the bondbetween the skin and the body of the article broken or will becompletely peeled.

The invention, therefore, has for its primary object the peeling offruit or vegetable articles in an automatic manner.

A further object of the invention is to provide an apparatus which willnot only result in automatic peeling but which will provide for animproved yield in the product, For example, with articles such astomatoes, the invention will provide for an increase in the number offancy tomatoes in the peeled product, the removal of a minimum skinthickness, and will reduce in general the losses involved in machineprocessing.

Another object of the invention is to provide an apparatus which allowstreating of fruit and vegetable articles at a lower temperature thanpreviously known high temperature processes to obtain satisfactory skinloosening prior to peel removal.

The above and other objects of the invention are attained in connectionwith a preferred embodiment of the invention as described herein, and asillustrated in the accompanying drawings, in which:

FIGURES 1 through 7 illustrate one form of the invention.

FIGURE 1 is a plan view of one form of the apparatus embodying theinvention;

FIGURE 2 is a side elevational view of the apparatus;

FiGURE 3 is an enlarged transverse sectional view through the apparatus;

FIGURE 4 is an enlarged fragmentary plan view taken as indicated by theline 4-4 in FIGURE 3;

FIGURE 5 is an enlarged side elevational view partially in section,illustrating the discharge end of the apparatus;

FIGURE 6 is a plan view of the portion of the apparatus shown in FIGURE5;

FIGURE 7 is an enlarged perspective view of one end of a roll having aspecial drive surface thereon;

FIGURES 8 through 11 illustrate a second form of the invention;

FIGURE 8 is an end elevational view partly in section of apparatus forcarrying out process;

FIGURE 9 is an elevational view of the velocity unit;

FIGURE 10 is a fragmentary sectional plan view taken in a planeindicated by the line 10-19 in FIGURE 9;

FIGURE 11 is a fragmentary longitudinal sectional view illustrating thearrangement of the upper and lower nozzle means with respect to thefruit being treated.

In order to enable a better understanding of the operation of theapparatus, the process which may be performed therein will be describedfirst. The process will be described with reference to the peeling oftomatoes, although it will be obvious that the process will beapplicable to other fruit and vegetable articles of the type commonlyprocessed in high temperature peeling operations, as 'well as others notnormally peeled in this manner.

Prior to the actual processing, as described herein, an article to bepeeled is first subjected to conventional washing and sorting operationsso that clean, defect-free articles are carried through the peelingprocess. In the case of tomatoes, as specifically described herein, thearticles may be cored prior to being subjected to the process, or theymay be cored after the process. The particular location of the coringstep will depend partially upon the character of the article beingtreated and plant conditions.

After the articles have been washed, sorted and treated in any desiredmanner in preparation for the peeling operation, the articles arecarried or transferred immediately into a heat application zone wherethey are subjected to a heating medium applied thereto in anadvantageous manner. The rate of travel through the heating zone iscontrolled with respect to the spec1fic article or tomatoes being peeledto provide the most desirable time of heat mg.

Desirably, the heating zone is substantially entirely enclosed, exceptfor the provision for entrance and exit of the articles, and thetreating and peeling medium or mediums, and this heating zone isprovided with a heating medium produced by combustion of a fuel. Theamount of gas or fuel and air introduced to the burner is such thatsubstantially complete combustion of fuel takes place, and a minimumamount of excess oxygen over and above the amount necessary for completecombustion is introduced. The treating atmosphere thus produced hasimparted thereto velocity to provide for peel separation or peel removaland to aid in heat transfer operations, as explained later in detail.

During passage of the product through the treating chamber, the firsteffect of the hot treating medium on tomatoes is to eifect a blisteringof the skin and skin cracking, this result being efiected in an improvedand desirable manner by virtue of the velocity of the heating medium.The heating medium immediately adjacent to the skin which is cooled byapplication thereto, is swept away immediately and replaced by anuncooled portion of the treating atmosphere. Because of the velocity ofthe treating medium the heating of the article to cause blistering issubstantially uniform so that the blistering effect takes place betweenthe outer layer of skin and the flesh of the tomato over substantiallyits entire surface. The result is a pufling out or expanding of the skinwith reference to the body of the tomato to provide a zone of slippage,which zone contains at least in part hot gases. Upon cracking the skin,it will within a short interval, suflicient for removal of the skin,return into engagement with the surface of the tomato. The skin portionwhich is loosened or rendered free or substantially free of the tomato,is the outer protective layer of the skin of the tomato, and the surfaceof the tomato still carries a tender, rough layer, which in conventionalprocesses would be removed as a part of the skin proper.

At the time of blistering or cracking of the skin, the tomatoes aresubjected to a velocity of the treating medium or a velocity of a fluidmedium which will, in effect, take hold of the free edges alongthe'cracks and peel back the skin to remove it in a rapid and effectivemanner. This fluid medium for effecting the actual peeling is preferablythe treating medium itself, if its velocity is sufficient for peelseparation or removal, or it maybe introduced as a separate entity atthe location along the path of travel of the products Where skinblistering and cracking of a major portion or substantially all of thetomatoes has occurred. This peeling medium therefore becomes elfectivewhile the skin is blistered and while'the zone of slippage between theblistered skin and the body of the tomato is still maintained.Preferablythe' treating and peeling medium is directed from above towardthe layer of tomatoes and the tomatoes,'positi'oned in valleys, arerotated during their treatment to insure exposure of all sides to thepeeling medium. The pressure effect of the medium resists any tendencyof the tomatoes to move out of.the valleys. The jets of the peelingmedium are preferably positioned. vertically at right angles to thedirection of travel of the articles. In one form of the invention thesejets are placed both above and below the tomatoes, and optimum resultshave been obtained with the upper jets inclined from the verticalsubstantially 15 degrees toward the exit end of the treating chamber,the lower jets in opposed relation thereto. For both skin conditioningand skin removal good results have been obtained with a set of nozzlespositioned entirely at one side of the articles, in which case thetomatoes are subject to a rotative driving effect so as to enable thetreatment of all sides and to provide a driving and a bumping action toenhance the peel removal.

After being subjected to the peeling medium the tomatoes are passedthrough a curtain of cooling water and discharged.

It is preferred to adjust the conditions of operation so that the skinwhich is removed from the tomato is carried by the conveyer from thetreating chamber and is removed from the conveyer. after discharge ofthe peeled tomatoes. Any skin fragments which become sufficiently burnedor charred so that they do not deposit on the conveyer are dischargedwith treating and peeling mediums and are subsequently separatedtherefrom where the gases are recirculated for reuse on the tomatoes. Inone form of .the invention steam is used as a peeling fluid and asrecirculation is employed, it serves as a source of additional moisturefor the treating medium. The steam also serves to wet the skins andthereby lower the temperature and retard char formation. Other hotgases, such as combustion products, may be employed as the peelingmedium. Preferably, however, the treating medium itself is used as thepeeling medium and recirculated with the addition of steam if desiredfor the purposes noted above.

The velocity of thetreating atmosphere is preferably not below 60 to 75miles perhour and has as an upper limit a velocity below that which willbodily remove flesh from a fruit or a vegetable article of soundcharacter. With fruit and vegetable articles this upper limit will varydepending upon the particular article being treated, its ripeness andcondition. Within the range of available velocities varying results willbe obtained at any given velocity depending on the ripeness andcharacter of the fruit, and the actual optimum'velocity for a givenfruit or vegetable article canbe determined by experimentation so thatoptimum conditions will obtain for a given fruit or vegetable articleduring the processing, as field conditions vary the quality of thearticle. Also, as common in canneries, different lots of articles arereceived from different localities and different fields so that theprocessing can be adjusted to the article as it is received, and inaccordance with the desired use of the tomatoes; i.e., as a fancy packor tomatoes for catsup as examples.

In general, the temperature of the treating atmosphere (plenumtemperature) can be between 600 and 1100 degrees n h Processing time canbe from 40. se n to as little as 5 seconds. With late. season,vine-ripened Pearson tomatoes, good results have been obtained with thetemperature of the treating atmosphere of 650 to 800 degrees F. (plenumtemperature) and with the processing time of 27 to 15 seconds. Thetemperature of the atmosphere contacting the tomatoes is from to 175degrees F. below plenum.

In processing tomatoes with the preferred form of apparatus shown inFIGURES l-7, effective peel separation or removal is obtained employingthe treating medium as the peel removing medium by providing holesspaced on 1. /2 centers transversely of the machine and on 3" centerslongitudinally of the machine in the direction of travel of the conveyerand these holes are spaced above the upper surface of the rollerssupporting the tomatoes for adequate clearance.

The velocity of the treating medium employed is given in the followingtable for different sizes of holes or orifices, as measured in theapparatus of FIGURES 1-7:

In processing tomatoes by another preferred form of the inventiondisclosed in FIGURES 811, effective peel removal is obtained by placinga transverse row of nozzles of inch opening spaced /2 inch apart andwith their discharge openings /2 inch from the lower surface of thetomatoes with a jet velocity as determined by a steam jet under a headof substantially 17 psi. gauge pressure which provides an estimatedvelocity at the jet of between 40,000 and 60,000 f.p.m. The upper row ofjets being spaced farther from the articles being treated for clearancepurposes, will have a correspondingly higher jet pressure to provide thesame steam velocity at the articles.

In actual operation, in a tomato processing plant, it has been founddifficult, due to the varying conditions of tomatoes being peeled, toobtain an adjustment of the conditions which will result in 100% skinseparation or peeling of the articles being treated, however, it hasbeen found possible to completely peel from 40% to 80%, and often ahigher percentage of the articles, with the remainder of the articleshaving over half of the peel separated or removed. Any remaining peel onthe tomatoes can be very easily slip-peeled so that any portions of theskin left can be very easily removed.

The above process in effect may be used to perform a sorting function toseparate fancy tomatoes suitable for solid pack from other tomatoes byallowing all tomatoes which have fragments or portions of skin remainingbecause of some defect on the tomato to pass on to another operation,and removing the tomatoes which are entirely peeled for the solid packoperation. This sorting function can be employed advantageously becausethe uniformity with which the tomatoes peel is a better measure ofquality and/ or maturity than the eye.

Referring to the form of the invention shown in FIGURES 1 through 7, theapparatus includes generally a treating unit 110, an atmospheregenerating unit 111, and a velocity imparting unit 112. The treatingunit is adapted to receive a high velocity treating and peeling 116. Theproduct being treated, tomatoes for example, 4

is carried through the treating chamber by a roller type conveyer 117which is trained about suitable idler and drive sprockets 118 (FIGURE 2)and is driven by a suitable variable speed motor 119.

The lower surface of the plenum chamber is formed by a partition plate121 (FIGURES 3 and 4) having a rectangular array of discharge apertures122 formed therein. To control the flow of the treating and peelingmedium to the partition plate 121., respective adjustable valve plates123 are provided having apertures 124 which can be aligned with theapertures 122. The amount of opening is controlled by means of a capscrew 126 rotatably connected to each plate 123 and engaged with a nut128 secured to the side wall. A spacer 127 about the screw 126 fixes theopen position of the plate 123.

At the upper end of the plenum chamber 113 an entrance pipe 131 foradditional air is provided, the opening being controlled by a damper 132having an adjusting handle 133".

The treating or peeling atmosphere enters the plenum chamber 113 throughan angle duct or housing 134 secured at one side of the plenum chamber113 and having a side opening 135 through which the heating meansextends. The means provided for supplying heat to the treatingatmosphere is in the form of a conventional gas gas burner 136 which isdisposed in axial alignment with the opening 135 and the entrance to theplenum chamber. The burner 136 receives a suitable gas and air mixturethrough suitable means including a pipe 137 and a blower 13-8.Preferably the ratio of gas to air is :such that the air supply issuificient for substantially complete combustion of the gas withoutproviding ex- -cess air, as disclosed for example in the co-pendingapplication of Roy M. Magnuson and Traver J. Smith, .Serial No. 394,919,filed November 30, 1953 for Process for Treating Fruits and Vegetables,now Patent No. 2,910,393. Suitable feed lines 141 and 142 are providedfor a pilot flame in the burner.

The angle housing 134 (FIGURES 2 and 3) has an -opening 139 at itsbottom which communicates with an upper discharge and or portion of ablower housing 146 having a suitable blower 147 therein driven through a.motor 148 by means of a belt and pulley coupling 14-9.

The exit passage from the treating chamber for the :gaseous treating andheating medium is through the apertures or openings provided between therolls 161 of the roller conveyer 117 and then downwardly into a cleaningchamber 151 through which the lower stretch of the roller conveyerextends. At the opposite end of the cleaning chamber, a transverse steampipe 152 is provided which effectively clears the treating atmosphere offree pieces of skin so that it enters the conduit 153 forming theentrance to the blower 148 in a substantially clean condition.

The roller conveyer has its rolls positively driven to provide adifferential speed relation between adjacent rolls which can be variedwith the entire roll assembly capable of variation by a variable speeddrive. Preferably the rolls, or certain of the rolls, are provided witha roughened surface to provide the desired amount of drive to thetomatoes undergoing the heat treatment to get the desired results, whichinclude a driving effect to enhance the skin slippage on the tomato.

The rolls 161 (FIGURES and 6) are connected by suitable chain links 156and have reduced end portions to engage the sprockets 118' andrespective rails 159 which extend through the treating chamber. Also,overlapping plates 157 are mounted on alternate rolls to provide abarrier at the edges of the treating chamber as seen most clearly inFIGURE 3.

As seen in FIGURES 5 and 6, the rolls are arranged in alternate serieswith the rolls in one series having a sprocket 162 at one end and therolls in the other series having a sprocket 163 at the opposite end. Thesprockets, 162 and 163 respectively, are engaged by respective drivechains 165 and 166 which are trained about suitable idler and drivesprockets including drive sprockets 167 and 168'. The sprockets 167 and168 on the drive shaft 169 of the respective chains having differentnumbers of teeth to provide a difference in speed or rotation betweenthe series of rolls. The drive shaft 169 is suitably driven from avariable speed motor 170. Suitable retaining strips 171 are provided formaintaining the chains engaged with the sprockets 162 and 163'.

Each alternate roll is provided with a special surface to obtain thedesired drive and in this case the surface is provided by a rectangularwire mesh screen of the desired size so that in eifect the surface ofthe roll is provided with a series of smooth round bars to eifect thedrive on the tomatoes or other articles. The covering for the rolls maytake the form of a conventional welded wire mesh having a rectangularopening of approximately 2" in length and 1" in width as shown forexample in FIGURE 7 and curved to conform to the diameter of the rolls.

Adjacent the entrance and exit of the roller conveyer 117 with respectto the treating chamber, transverse steam pipes 176 and 177 (FIGURES 2and 3) are provided having a row of openings directed generallydownwardly and slightly inwardly toward the treating chamber, thusproviding a steam barrier in the entrance and exit ends of the treatingchamber and providing additional moisture in the treating medium ifdesired.

The machine is first set in operation and the temperature and treatingmedium conditions allowed to become steady at the desired conditions forthe particular tomatoes to be processed. This would include theadjustment of the roll speed of the rollers 161, the adjustment of thespeed of the conveyer through the treating chamber, the temperatureconditions, the blower speed and the amount of steam to be injectedthrough either one or both of the pipes 176 and 177. With the machinethus conditioned, tomatoes are fed into the feed end of the rollerconveyor and carried through the treating chamber being subjected to thedownwardly moving treating gases or medium and at the same time beingrolled over and over by the difierential drive imparted thereto from therolls.

The treating medium itself, being employed also as a peeling medium inthis form of the invention, the first effect of the treating medium onthe tomatoes is to effect a blistering of the skins and in effect aseparation of the skins from the body of the tomato. Because of the hightemperature and high velocity this blistering action is of a differentcharacter than ordinary skin loosening and operates with reference to athin outer layer of skin. Because of the varying conditions of thetomatoes, as to ripeness, for example, this blistering will occur atdifferent positions along the treating chamber in accordance with thelength of time required for a particular tomato. However, at the timewhen blistering does occur, i.e., when skin separation is obtained, thetreating medium moving at a velocity in excess of 60 to 75 miles perhour will seize any skin at the point of rupture and strip it free ofthe tomato. If the skin at the time of rupture is not in a position tobe caught by the peeling medium, it may settle back against the articleand require later picking off by hand or mechanical means. The peelremoval is enhanced by the action of the peeling rolls where thealternate rollers carrying the wire mesh coating are traveling at agreater speed than the other rolls. This gives a selective amount ofdrive with a certain dragging action which produces slippage of the skinand thereby enhances the peeling action.

Tomatoes which have the peel removed, rather than merely separated, maybe still subjected for a time to the hot treating medium, but this willnot produce over- .cooking of the tomatoes because of the moistcondition of the body of the article which maintains an insulating layerof vapor at 212 Fahrenheit, and the length of time they remain subjectedto the treating atmosphere is insufiicient to produce any appreciabledrying of the tomato.

Referring to the modification shown in FIGURES 8 through 11, theapparatus includes generally a treating unit 10, an atmospheregenerating unit 11, and a velocity imparting unit 12. The treating unit10 is adapted to receive a high velocity treating atmosphere from thecombined operations of the units 11 and 12, and for this purpose isprovided with upper and lower plenum chambers 13 and 14 respectivelyabove and below a treating chamber 16. The product being treated,tomatoes, for example, is carried through the treating chamber by aperforated or mesh type conveyer 17 which is trained about suitablesupporting drums 18, only one of which is shown in FIGURE 4. Therespective partitions between the plenum chambers 13 and 14 and thetreating chamber 16 are formed by similar partition plates 21 having arectangular array of discharge nozzles 22 comprising short sections ofpipe secured in the partition plates 21 to direct the flow of thetreating atmosphere. Preferably, the pipes in the respective upper andlower partition plates 21 are offset with respect to each other so thatno jets are in direct opposed relation.

The treating chamber is also provided near its discharge end with peelremoving means comprising respective upper and lower transverse pipes 23and 24 having a series of perforations therein to direct the peelremoving medium. Preferably, the upper pipe 23 has its perforationspositioned at about from the vertical toward the discharge end of themachine While the pipe 24 is inclined similarly toward the entrance end,so that the jets issuing therefrom are in opposed relation. However,vertical positioning of the perforations with respect to the conveyerperforms satisfactorily. The pipes 23 and 24 are suit-ably connected toa source of supply of a peeling medium such as steam under pressure orother suitable gas or fiuid medium whereby a desired velocity of thepeeling medium is provided.

The treating or conditioning atmosphere enters the plenum chambersthrough a conduit 31 (FIGURE 8) at one side of the treating chamber, theconduit 31 leading from a Venturi passage 32 provided by an annularthroat member 33 of suitable heat resisting material. The passage formedin the conduit 31 is divided by a V-shaped bafiie 34 to separate thetreating atmosphere into two streams for the respective plenum chambers.

Means are provided for supplying heat to the treating atmosphere andalso for supplying additional atmosphere in the form of a conventionalgas burner 36 (FIGURE 6) which is disposed in axial alignment with thethroat member 33 and receives a suitable gas and air mixture through apipe 37 from a blower 38, providing the source of air, and a pipe 40leading from a gas pressure regulator 39 and having its end 40a disposedwithin the pipe 37. Preferably. the ratio of gas to air is such that theair supply is sufficient for substantially complete combustion of thegas without providing excess air. Suitable pilot lines 41 and 42 areprovided for a pilot flame in the burner.

The burner 36 discharges into a housing 46 which is connected to theburner and to the throat member 33, and forms a suitable involutepassage with respect to burner 36 and the throat member 33. The upperend of this housing 46 is connected through duct 47 with the airvelocity unit 12 having a conventional blower 48 therein driven by motor49. The inlet to the air velocity unit 12 comprises a right angleconduit 51 extending between the air velocity unit 12 and with thetreating unit 10. A valve-controlled inlet 50 (FIGURE 9) is provided asa source of additional air in the treating medium if desired. Treatingmedium discharged from the plenum chambers and the peeling mediumdischarged from the pipes 23 and 24 passes upwardly at either end of theupper plenum chamber 13 for return 8 through housing 52 of the unit 10and the conduit 51 to the velocity unit 12.

For cooling of the surface of the product being peeled, a perforatedwater pipe 53 is positioned transversely about the conveyer 17 ahead ofa suitable discharge ramp to which the product is delivered by theconveyer 17.

The nozzles or perforations of the pipes 23 and 24 are preferably in asubstantially continuous series above and below the belt, /2 inchtransverse spacing being found as sufiicient to obtain a good peelingaction. As shown, the upper series of nozzles are located to be spaced 2inches from the tomatoes, and the lower series /2 inch. Preferably, theheat penetration, due to the velocity of the heat-treating medium andthe time during which the articles are subjected to it, is sufficientonly to allow the desired heat penetration for blistering. Any amount ofheating of the layer of the fieshimmediately adjacent to the skin isimmediately cooled bythe water curtain.

The following data is from actual runs on late season tomatoes:

1 Plenum temperature is measured at a central location in one of theplenum chambers.

RUN P-3 This run is comparative with run Y-6 with the labor being paidon an incentive scale. Machine Data:

Plenum temperature 800.

Gas air mixture 8.3" H 0.

Fan differential 6.4" H 0.

Fan r.p.m 2290. Steam (treating chamber jets) Lower 15#; upper 22#:

Treating chamber temperature 625.

Times interval 12 sec.

Peeling data: Raw weight (calculated with 7% machine and core loss) lbs3867.5 Total peeled weight lbs 3379.5 Weight of fancies lbs 2237.0Weight of standards 1bs 1147.5 Weight of bypass lbs 831.0 Weight of p l-lbs 235.0 Percent peeled by process 60 RUN 315 The two jets in thetreating chamber were turned 15 in the direction of travel of thetomatoes.

Data:

Run I II Fan Sp 2190 2190 Temp. F (Plenum) 760 760 S.P. 4. 5 4. 5 GAM"H2O. 12.7 12. 7 Steam (approx 20 20 Time 2O 25 Results:

I. 90% peeled by the process. Good quality, some char but not anobjectionable amount. The peelability was the best achieved to date.

id mon orifice, and means for heating said gases including a burnerhaving its outlet directed toward said orifice.

2. In a peeling machine, means providing a treating chamber, an articleconveyer passing through said treat- II. 80% peeled. Some char. Verygood quality ing chamber, means providing respective upper and lowerwith the peelability better than run No. I. plenum chambers above andbelow said treating cham- TEST her, a partition between each of saidplenum chambers and said treating chamber comprising an array of noz-Small lots of 25 tomatoes were processed at various zles for directingthe flow of gas from the plenum chamemp f speeds and tune Intervals tooffer a 0 her to the treating chamber, means including high velocitydirect comparison of the efiec f veloc y n he pe lirnpelling means forsupplying a high velocity stream of y, q y, and percent peeled. gases toeach of said plenum chambers, and means for Static Peel- No. R.P.M.Plenum Pressure (Inches Time Percent ability Temp., (Inches H) (Sec)Peelcd 01' re- H2O) mainder 2,190 500 6.4 8.4 33 4 Fair. 2, 190 600 6. 78. 4 20 43 Good. 2,190 700 6.3 10.8 16 33 Do. 2,190 800 2, 190 900 6. 011. 4 12 42 Do. 2, 190 1, 000 6. 0 11.4 12 44 Poor. 2,290 70 6.0 7.2 02, 290 610 6. s s. 0 30 43 Fair. 2, 290 710 6. 4 8. 4 25 25 Do. 2, 290810 6. 0 8. 2 15 30 Poor. 2, 290 810 6. 0 s. 2 27 60 Good. 2, 290 900 5.4 9. 2 14 45 Poor. 2, 290 1, 000 5. 4 11. 4 12 10 Bad. 1, 570 520 3. 24. 5 30 0 Good. 1, 570 610 s. 0 4. 2 30 8 Fair. 1, 670 710 2. s 4. a 250 D0. 1, 570 810 2. 6 4. 2 20 8 Good. 1, 570 920 2. 6 5. 0 14 a Do. 1,570 1,000 2. 6 5. 4 11 4 Do.

The above data on runs was taken with the equipheating said gases, saidheating means including a burner ment illustrated in FIGURES 8 to 11.providing substantially the entire supply of said gas.

The following figures are taken fronractua l production 3. In a peelingmachine, a substantially enclosed treatruns on diiferent days with theequlpment shown in ing chamber, a conveyer passing therethrough, anarray FIGURES 1 to 7. of nozzles directed substantially at right anglestoward said conveyer, means for supplying said nozzles with a AverageAverage AYerage Average 40 high velocity gaseous stream as a treatingmedium, a Pisa. stress. is; rinter nozzles seeding transversely of saidHours Woman Pound Peeled I-Iour veyer ad acent the discharge end of saidarray of nozzle mamas means, and means for supplying said series ofnozzles with a high velocity fluid medium, the velocity of said 3% 2:58822? g: fluid medium being substantially greater than the velocity 9545.0 .00663 6.56 of. said treating medium.

4. In a peeling machine, means forming a treating Other articles can besuccessfully peeled in the above chamber, means fom'llllg {espectlve ppand lower manner, for example, With White onions, a plenum (re plenumchambers at elther side of the treating chamber, perature of from 600 to650 degrees F., with the given F Outlet duct lwdlng f the trefltlng anvelocities and a treating time of from 11 to 7 seconds, duct common toSaid Plenum chamber? hlgh V5106 the onions were from 40% to 50%completely peeled y p e means germs-fled betweensald ducts, and and onthe balance of onions, the skin could be very high temPeTatureheaflnsmeans F QP g a gas burner easily slip-peeled. With yellow onions,a plenum teme e the outlet of 531d veloclty lmpelllng means and peratureof from 750 to 800 degrees F. is used with a Sald dl tv treating time offrom 18 to 12 seconds. The results were 5 fi pp for fllllt and vegiablearmies from 50% to completely peeled with easy slipcompflsmg asllbstalltlally enclosed i g h peeling of the balance of the onions. Inreferring to a y Pf therethrqugh for CaITYIIIg articles 'f the peelingof onions, the peel referred to is actually be Pf Sald Chamber havmg atleast one Wall of Sald an inner layer which consists partially of adried portion 60 tfeatlng Chamber mp offill array of T19R16 and paptiauyf an undried edible portion directed toward articles on said conveyer, hgh veloclty While I have described preferred apparatuses it will p lmeans for pp y a gaseous tramlg 111641111111 be obvious that they arecapable of variation and modi- 110 ZZ1eS, high fifrmpefatllfe heatlflgmeans f fication within the scope of the appended claims. sald treatmg msaid high temperature heating What is clajmedis: means comprising a gasburner supplymg the ma or 1. In a peeling machine, means providing atreating Portlon 0f sfild gaseous chamber, an article conveyer passingthrough said treat- 6. peeling apparatus for fruit and vegetablearticles ing chamber, means providing respective upper and lowercomprising a substantially enclosed treating chamber plenumchambersabove and below said treating chamopen to atmosphenc pressure, aconveyer extendmg thereber, a partition between each of said plenumchambers through for carrying a layer of articles to be peeled, said andsaid treating chamber comprising an array of nozchamber havingrespective upper and lower walls eacn zles for directing the flow of gasfrom the plenum chamcomprising an array of nozzle means d sposedsubstanber to the treating chamber, means including high velocity tiallyat nght angles to sa1d conveyer, high veloc ty 1mimpelling means forsupplying a high velocity stream pelling means for supplying a fluidtreat ng medium to of gas to each f id Plenum ghambgrs thm gh a g msaidnozzles, and lugh temperature heating means for 1 i said treatingmedium, said high temperature heating means comprising a gas burnersupplying the major portion of said gaseous medium.

7. In a peeling machine, means forming a treating chamber, means forminga plenum chamber at one side of the treating chamber, a partition wallbetween said plenum chamber and said treating chamber comprising anarray of nozzles, an inlet duct to said plenum cham ber, high velocityimpelling means connected to said inlet duct, an outlet duct leading romsaid impelling means to said inlet duct, and a gas burner extending intosaid outlet duct from a side thereof and at a location between said highvelocity impelling means and said inlet duct.

8. In a peeling machine for fruit and vegetable articles, means forminga treating chamber, a conveyer for carrying articles to be treatedthrough said chamber, means forming a substantially closed circulatingpath for a gaseous treating medium, said path including said chamber,means along said path for imparting a high velocity to the mediumcirculating through said path, and means along another portion of saidpath remote from said chamber for heating said medium to a hightemperature before impact thereof with the articles, said heating meanscomprising a gas burner supplying the major portion of said gaseoustreating medium.

9. In a peeling machine, means forming a treating chamber, a plenumchamber 'at one side of the treating chamber, means forming acirculating path for the flow of a gaseous treating medium, said pathincluding said treating chamber and said plenum. chamber, high velocityimpelling means in said path having a discharge path portion connectedto said plenum chamber, and high temperature heating means forintroducing heat and hot gases into the discharge from said highvelocity impelling means.

10. In a peeling machine, means forming a treating chamber, a plenumchamber at one side of the treating chamber, means forming a circulatingpath for the flow of a gaseous treating medium, said path including saidtreating chamber and said plenum chamber, high velocity impelling meansin said path having a discharge path portion connected to said plenumchamber, means forming an involute passage connected to said pathportion and discharging axially into said plenum chamber, and hightemperature heating means having an outlet leading into said involutepassage and disposed axially thereof.

11. In a peeling machine, means forming a treating chamber, a plenumchamber at the upper side of the treating chamber, a roller conveyer atthe lower side of the treating chamber having article supporting rolls,driving means for said rolls, means forming a circulating path for theflow of a gaseous treating medium, said path including said treatingchamber and said plenum chamber, high velocity impelling means in saidpath having a discharge path portion connecting to said plenum chamber,and high temperature heating means for introducing heat and hot gasesinto said medium as it passes through said discharge path portion.

12. In a peeling machine, means forming a treating chamber, a plenumchamber at the upper side of the treating chamber, a roller conveyer atthe lower side of the treating chamber having article supporting rolls,variable speed driving means for said rolls, other variable speeddriving means for said conveyer, means forming a circulating path forthe flow of a gaseous treating medium, said path including said treatingchamber and said plenum chamber, high velocity impelling means in saidpath having a discharge path portion connected to said plenum chamber,and high temperature heating means for introducing heat and hot gasesinto said medium as it passes through said discharge path portion.

13. In a peeling machine, means forming a treating chamber, a plenumchamber at the upper side of the treating chamber, a roller conveyer atthe lower side of the treating chamber, said roller conveyer comprisingalternate series of rolls having different surface characteristics forimparting different effective drives to articles supported thereon,driving means for rolls including means for imparting differentperipheral speeds to said respective series of rolls, means forming acirculating path for the flow of a gaseous treating medium, said pathincluding said treating chamber and said plenum chamher, high velocityimpelling means in said path having a discharge path portion connectedto said plenum chamber, and high temperature heating means forintroducing heat and hot gases into said medium as it passes throughsaid discharge path portion.

References Cited in the file of this patent UNITED STATES PATENTS1,222,008 McIntyre Apr. 10, 1917 1,647,872 Leavitt Nov. 1, 19271,992,398 Ryder Feb. 26, 1935 2,218,466 Gray et al. Oct. 15, 19402,515,025 Vahl et a1. July 11, 1950

